<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
    <div id="app">
        <div :class="classes"></div>
    </div>
    <script src="https://unpkg.com/vue@2.6.1/dist/vue.min.js"></script>
    <script>
        var app = new Vue({
            el: '#app',
            data:{
              'isActive': true,
              'error': null
            },
            computed:{
                classes: function () {

                    return{
                        active: this.isActive && !this.isError,
                        'text-fail': this.error && this.error.type === 'fail'
                    }
                }
            }

        });
        console.log(true && !null);

    </script>
</body>
</html>